The present invention relates generally to the field of connecting mechanisms for fixedly joining together a length of tubing to a medical liquid container. Connectors of this general type are capable of a wide variety of uses in medical applications. The connector of the present mechanism was developed specifically for use in continuous ambulatory peritoneal dialysis.
Connectors have been used for many years to effectuate rapid and effective junctions between pieces of tubing. A requirement of such connectors is that a fluid-tight seal be obtained. Another requirement is that the connection, once made, should be strongly resistent to inadvertent disengagement, but should be readily disengageable when desired by simple and rapid manual manipulation.
It has long been known that fluid-tight connections are provided by a pair of tapered members, one including a female portion having an internal opening with an inner conical tapered sealing surface, and the other member including a male portion having a protrusion with an outer conical, matingly tapered, sealing surface. However, in order to ensure the desired fluid-tight connection, the members must be forced longitudinally together, preferably with a slight twisting motion, with sufficient pressure to ensure that the locking friction angle of the tapered surfaces are forced into intimate frictional contact. Even when the desired intimate contact providing the fluid-tight connection is established, an inadvertent, longitudinal tugging between the tubes associated with the two members is often sufficient to disengage the connection and break the seal.
Similarly, the use of piercing pins adapted for connection to medical liquid containers is commonly known in the art. However, such piercing pins are commonly inserted into a length of flexible tubing extending from the containers in a press-fit connection which is difficult to disengage while in use. Thus, the problem heretofore unsolved by the prior art is the provision of simplified means to ensure the intimate frictional contact sufficient to provide fluid-tight connection and to preclude relative longitudinal motion tending accidentally to disengage the sealing surfaces, while at the same time allowing selective disengagement with relatively easy manual manipulation. At the same time, maintaining the connection in an aseptic condition is also desirable.
Examples of attempts to overcome this problem are the devices shown in U.S. Pat. Nos. 4,201,406; 4,030,494; and U.S. No. De. D-229,518. Despite these efforts, in the field of peritoneal dialysis, a relatively high rate of peritonitis has been found, which, it is suspected, is due to the passage of microorganisms through the connector and into the peritoneal cavity of the patient. In order to prevent such microbial contamination, it is an advantage of the present invention to provide a novel connecting device which maintains the connection between a piercing pin and a container port in a sealed configuration. As an additional feature, the present connector may include an aseptic barrier positioned within the device which provides a barrier against the invasion of microbial contaminants. It is an additional advantage of the present invention to provide such a connecting device which is relatively easy to manipulate and inexpensive to manufacture.